Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
  • A61F13/512—Topsheet, i.e. the permeable cover or layer facing the skin characterised by its apertures, e.g. perforations
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/20—Tampons, e.g. catamenial tampons; Accessories therefor
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
  • A61F13/5116—Topsheet, i.e. the permeable cover or layer facing the skin being formed of multiple layers
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
  • A61F13/512—Topsheet, i.e. the permeable cover or layer facing the skin characterised by its apertures, e.g. perforations
  • A61F13/5126—Topsheet, i.e. the permeable cover or layer facing the skin characterised by its apertures, e.g. perforations characterised by the planar distribution of the apertures, e.g. in a predefined pattern
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F2013/51002—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers with special fibres
  • A61F2013/51023—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers with special fibres being polymeric fibres
  • A61F2013/51033—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers with special fibres being polymeric fibres being hydrophilic
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
  • A61F13/5116—Topsheet, i.e. the permeable cover or layer facing the skin being formed of multiple layers
  • A61F2013/51173—Topsheet, i.e. the permeable cover or layer facing the skin being formed of multiple layers with the combination of polymeric films
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F13/00—Bandages or dressings; Absorbent pads
  • A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
  • A61F13/51—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the outer layers
  • A61F13/511—Topsheet, i.e. the permeable cover or layer facing the skin
  • A61F13/512—Topsheet, i.e. the permeable cover or layer facing the skin characterised by its apertures, e.g. perforations
  • A61F2013/5127—Topsheet, i.e. the permeable cover or layer facing the skin characterised by its apertures, e.g. perforations characterized by the dimension of apertures

Definitions

• the present invention relates to absorbent articles particularly sanitary napkins having layered topsheets.
• a first layer receiving the liquids to be absorbed comprises apertures of at least 1.4 mm 2 area in a film within the longitudinal center of the film.
• a second film layer provides liquid transfer to an absorbent structure through apertures of less than 1.4 mm 2 area. Additionally the second layer provides visual masking of absorbent liquids in the area of the large apertures of the first topsheet layer.
• the apertures in the first layer preferably are also only provided in the transverse center of the film. The distribution of the apertures leaves a certain longitudinal side edge and preferably transverse end edge of the topsheet free of the large apertures to improve comfort of the product during use.
• Sanitary articles such as sanitary napkins, baby diapers, absorbent inserts, and absorbent adult incontinence articles are well-known in the art.
• all these articles comprise a wearer facing surface ("internal") and a garment facing surface (“external”).
• the wearer facing surface receives from the wearer of such articles liquids, bodily discharges such as menses, to be absorbed.
• the wearer facing surface In order for the article to store the liquid the wearer facing surface has to be liquid permeable while maintaining integrity of the outer wearer facing surface of the absorbent article.
• This wearer facing surface is provided by a topsheet and is the one which comes into contact with the wearer's skin.
• topsheets in the art of absorbent articles are non-woven fabrics, woven fabrics or films.
• Films have to be rendered permeable by aperturing.
• Fabrics or non-woven fabrics are made of fibers which by their nature provide non-linear apertures of varying and changing size depending on the selected direction for liquid transport through them.
• Films are often made of polymeric material and typically comprise apertures which have been engineered to provide certain characteristics. These apertures can vary in shape and size.
• the walls of the apertures define the amount of extension - if any - beyond the plane of the film thickness and the direction of such extensions.
• the film apertures also can be provided in the shape of a funnel.
• a typical topsheet made of polyethylene film has been successfully used in sanitary articles and adult incontinence products as well as inserts and baby diapers.
• One problem remaining is the total amount of liquid capable of passing through such a topsheet under usual usage conditions due to the total amount of open area of all apertures and individual aperture size and shape in particular.
• Exceptionally large apertures increase the liquid passage rate but pose the problem of masking because liquids such as menses remain visible to the wearer, which is considered undesirable.
• large apertures promote a backflow of absorbed liquid, so called rewet, which is undesirable.
• Small individual apertures on the other hand cannot provide the liquid passage characteristics required to let liquids of high surface tensions pass through; this can be a problem in an absolute sense for very small apertures or cause too low a rate of liquid flow.
• the present invention does not attempt to provide selection criteria for this balancing problem but to shift the balance for this problem in order to obtain improved absorbent articles in respect to their capability of fast liquid intake as well as rewet and masking of the liquid received while maintaining acceptable characteristics of material strength and other considerations for topsheets.
• the present invention provides an absorbent article having all the benefits of a large aperture film topsheet without the comfort, masking, and rewet problems of the prior art.
• the absorbent article comprises a laminate topsheet having a wearer facing surface and a garment facing surface.
• the topsheet comprises a first and second layer which are preferably joined to each other.
• An absorbent article generally further comprises a backsheet and an absorbent structure alternatively called absorbent core placed between the topsheet and the backsheet.
• Two types of absorbent articles have to be distinguished according to the present invention: those having wings or side wrapping elements which comprise at least the first layer of the topsheet and those which do not.
• the wings or side wrapping elements which are preferred as such can generally be provided by extension of the backsheet, the topsheet, one or several layers of the topsheet or the backsheet, or combinations thereof.
• wings or side wrapping elements can be provided by materials separately joined to the article. Wings or side wrapping elements are folded along a bending axis around the side edge of the leg opening of an undergarment.
• the wearer facing surface of the topsheet is most decisive in providing wearer comfort because it is as intinitly in contact with the wearer's skin as the side edge of the undergarment.
• the absorbent structure can include the following components: (a) optionally a primary fluid distribution layer preferably together with a secondary optional fluid distribution layer; (b) a fluid storage layer; (c) optionally a fibrous ("dusting") layer underlying the storage layer; and (d) other optional components.
• One optional component of the absorbent structure according to the present invention is a primary fluid distribution layer and a secondary fluid distribution layer.
• the primary distribution layer typically underlies the topsheet and is in fluid communication therewith.
• the topsheet transfers the acquired fluid to this primary distribution layer for ultimate distribution to the storage layer.
• This transfer of fluid through the primary distribution layer occurs not only in the thickness, but also along the length and width directions of the absorbent product.
• the also optional but preferred secondary distribution layer typically underlies the primary distribution layer and is in fluid communication therewith. The purpose of this secondary distribution layer is to readily acquire fluid from the primary distribution layer and transfer it rapidly to the underlying storage layer. This helps the fluid capacity of the underlying storage layer to be fully utilized.
• the fluid distribution layers can be comprised of any material typical for such distribution layers. In particular fibrous layers maintain the capillaries between fibers and even when wet are useful as distribution layers.
• the fluid storage layer can comprise any usual absorbent material or combinations thereof. It preferably comprises absorbent gelling materials usually referred to as “hydrogel”, “superabsorbent”, “hydrocolloid” materials in combination with suitable carriers.
• the absorbent gelling materials are capable of absorbing large quantities of aqueous body fluids, and are further capable of retaining such absorbed fluids under moderate pressures.
• the absorbent gelling materials can be dispersed homogeneously or non-homogeneously in a suitable carrier.
• the suitable carriers provided they are absorbent as such, can also be used alone.
• Suitable absorbent gelling materials for use herein will most often comprise a substantially water-insoluble, slightly cross-linked, partially neutralized, polymeric gelling material. This material forms a hydrogel upon contact with water.
• polymeric gelling material can be prepared from polymerizable, unsaturated, acid-containing monomers which are well-know in the art.
• Suitable carriers include materials which are conventionally utilized in absorbent structures such as natural, modified or synthetic fibers, particularly modified or non-modified cellulose fibers, in the form of fluff and/or tissues. Suitable carriers can be used together with the absorbent gelling material, however, they can also be used alone or in combinations. Most preferred are tissue or tissue laminates in the context of sanitary napkins/panty liners.
• An embodiment of the absorbent structure made according to the present invention comprises a double layer tissue laminate formed by folding the tissue onto itself. These layers can be joined to each other for example by adhesive or by mechanical interlocking or by hydrogen bridge bonds. Absorbent gelling material or other optional material can be comprised between the layers.
• Modified cellulose fibers such as the stiffened cellulose fibers can also be used.
• Synthetic fibers can also be used and include those made of cellulose acetate, polyvinyl fluoride, polyvinylidene chloride, acrylics (such as Orlon), polyvinyl acetate, non-soluble polyvinyl alcohol, polyethylene, polypropylene, polyamides (such as nylon), polyesters, bicomponent fibers, tricomponent fibers, mixtures thereof and the like.
• the fiber surfaces are hydrophilic or are treated to be hydrophilic.
• the storage layer can also include filler materials, such as Perlite, diatomaceous earth, Vermiculite, etc., to improve liquid retention.
• the storage layer can nevertheless be locally homogeneous, i.e. have a distribution gradient in one or several directions within the dimensions of the storage layer.
• Non-homogeneous distributions can also refer to laminates of carriers enclosing absorbent gelling materials partially or fully.
• An optional component for inclusion in the absorbent structure according to the present invention is a fibrous layer adjacent to, and typically underlying the storage layer.
• This underlying fibrous layer is typically referred to as a "dusting” layer since it provides a substrate on which to deposit absorbent gelling material in the storage layer during manufacture of the absorbent structure. Indeed, in those instances where the absorbent gelling material is in the form of macro-structures such as fibers, sheets or strips, this fibrous "dusting" layer need not to be included. However, this "dusting" layer provides some additional fluid-handling capabilities such as rapid wicking of fluid along the length of the pad.
• the absorbent structure according to the present invention can include other optional components normally present in absorbent webs.
• a reinforcing scrim can be positioned within the respective layers, or between the respective layers, of the absorbent structure.
• Such reinforcing scrims should be of such configuration as not to form interfacial barriers to fluid transfer. Given the structural integrity that usually occurs as a result of thermal bonding, reinforcing scrims are usually not required for thermally bonded absorbent structures.
• odor control agents Another component which can be included in the absorbent structure according to the invention and preferably is provided close to or as part of the primary or secondary fluid distribution layer are odor control agents. Active carbon coated with or in addition to other odor control agents, in particular suitable zeolite or clay materials, are optionally incorporated in the absorbent structure. These components can be incorporated in any desired form but often are included as discrete particles.
• the backsheet primarily prevents the exudates absorbed and contained in the absorbent structure from wetting articles that contact the absorbent product such as underpants, pants, pyjamas and undergarments.
• the backsheet is preferably impervious to liquids (e.g. menses and/or urine) and is preferably manufactured from a thin plastic film, although other flexible liquid impervious materials can also be used.
• liquids e.g. menses and/or urine
• the term "flexible” refers to materials that are compliant and will readily conform to the general shape and contours of the human body.
• the backsheet also can have elastic characteristics allowing it to stretch in one or two directions.
• the backsheet typically extends across the whole of the absorbent structure and can extend into and form part of or all of the preferred sideflaps, side wrapping elements or wings.
• the backsheet can comprise a woven or non-woven material polymeric films such as thermoplastic films of polyethylene or polypropylene, or composite materials such as a film-coated non-woven material.
• the backsheet is a polyethylene film having a thickness of from about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mils).
• Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation P18-0401 and by Ethyl Corporation, Visqueen Division, of Terre Haute, Indiana, under the designation XP-39385.
• the backsheet is preferably embossed and/or matte finished to provide a more clothlike appearance. Further, the backsheet can permit vapors to escape from the absorbent structure, i.e. be breathable, while still preventing exudates from passing through the backsheet. Also breathable backsheets comprising several layers, e.g. film plus non-woven structures, can be used.
• the topsheet is the topsheet
• joind encompasses configurations in which the first layer is directly secured to the second layer by affixing the first layer directly to the second layer; configurations in which the first layer is indirectly secured to the second layer by affixing the first layer to intermediate layer(s) which in turn is (are) affixed to the second layer. Both layers are preferably joined to each other across at least 25 % of their total interface.
• the layers of the topsheet can be joined together by adhesives, stitching, heat and/or pressure bonds, dynamic mechanical bonds, ultrasonic bonds, intermingling or entanglement of the structural elements comprising the layers of the topsheet, such as by extruding one layer onto another, or by any other means known in the art.
• the topsheet comprises a first passage layer which provides the user facing surface of the topsheet and a second passage layer between the first passage layer and the absorbent structure.
• the topsheet as a whole and hence each layer individually needs to be compliant, soft feeling, and non-irritating to the wearer's skin. It also can have elastic characteristics allowing it to be stretched in one or two directions.
• the topsheet or each of its layers separately extends across the whole of the absorbent structure and can extend into and form part of or all of the preferred wings or side wrapping elements of the absorbent article according to the present invention.
• the first passage layer is provided by a film material having apertures which herein are referred to as “large apertures” and optionally apertures which herein are referred to as “small apertures”. These apertures are provided to facilitate liquid transport from the wearer facing surface towards the absorbent structure.
• the large apertures have an individual open area of from 1.4 mm 2 , to 3.0 mm 2 and preferably from 1.5 mm 2 to 2.5 mm 2 .
• the total open area of the large apertures in the upper passage layer excluding all other liquid transport apertures should be in the range from 5% to 20%, preferably from 10% to 20% of the surface area of the first layer of the topsheet.
• the optional small apertures in the first layer of the topsheet of the absorbent article have an individual open area of less than 1.4 mm 2 and typically not smaller than 0.15 mm 2 . Apertures which are even smaller are usually not suitable for liquid transport at all and would only function as gas permeable apertures for example for breathability purpose. Preferably, the optional small apertures are in the range of 0.25 mm 2 to 0.4 mm 2 .
• the apertures are preferably substantially circular or polygonal. Their shape is limited by having a ratio of the largest to the smallest inner diagonal length in the range between 1 and 6, preferably 1 and 3.
• the total open area of all liquid transport apertures in the first layer is in the range of 10% to 40%, preferably 15% to 35% of the total area of the first layer.
• Topsheets according to the present invention have a non-homogeneous distribution of the liquid passage ways or apertures across the wearer facing surface of the topsheet. It recently has been found that a topsheet comprising large apertures has a higher tendency of being considered to cause discomfort to some wearers of sanitary napkins comprising such topsheets.
• the absorbent article and all main components have a longitudinal axis which is parallel to a plane which would bisect a wearer of such an article into right and left side. Also the absorbent article has a transverse axis which is perpendicular to the longitudinal axis and within the same plane as the article.
• longitudinal center refers to the center of the article and extends parallel to the longitudinal axis.
• transverse center refers to the center of the article and extends parallel to the transverse axis.
• the topsheet according to the present invention requires that the large liquid transport apertures mentioned above are only distributed in the longitudinal center 90 % of the largest transverse width of the first passage layer of the topsheet for articles not having wings or side wrapping elements which comprise integral extensions of said first passage layer of said topsheet.
• these large apertures are distributed in the longitudinal center 80 %, most preferably 70 % of the largest transverse width of the first passage layer of the topsheet for articles not having wings or side wrapping elements which comprise integral extensions of said first passage layer of said topsheet.
• the first layer of the topsheet according to the present invention can extend into the wings or side wrapping elements. In such a case a distance of 5 %, preferably 10 %, of the smallest transverse distance between said bending axes, should be left void of large liquid transport apertures around each of the bending axes of each wing or each side wrapping element.
• the apertured topsheet it is possible to only provide large apertures in the region of the longitudinal center 95 %, preferably 85 %, most preferably 70 %, of the smallest transverse distance between the bending axes of the wings or side wrapping elements to satisfy the more specific requirement stated above according to which large apertures in the first layer of the topsheet are possible even if that layer is integral with wings or side wrapping elements.
• an embodiment of the present invention has the large apertures only distributed in the transverse center 80 %, preferably 65 %, most preferably 50 % of the largest longitudinal length of the wearer facing surface of the article.
• An additional benefit obtainable from the basic or preferred embodiments according to the present invention is the concentration of large liquid transport apertures towards the center of the absorbent article such that more open area is placed where liquid acquisition is most probable. This then provides a benefit in absorbency of the respective absorbent article.
• the large liquid transport aperture distribution towards the center of the article can be achieved by providing the respective aperture distribution in the first film layer of the topsheet by selective aperturing in particular if the first layer has generally the same extension as the article.
• An alternative can be of course to only provide the first film layer of the topsheet in the area where large liquid transport apertures are desired with the second layer of the topsheet providing the outer, wearer contacting layer of the topsheet outside that area. This is possible for both articles with or without wings or side wrapping elements which comprise integral extensions of the first layer.
• liquid transport apertures can be formed in the film such that the walls of the apertures extend beyond the plane of the surface of the basic film, i.e. the film surface, before the film is apertured.
• the direction of these extending walls in the absorbent article is towards the garment facing surface of the article.
• the amount of extension of the walls of the apertures in the first layer is at least 0.3 mm beyond the film surface form which the walls of the apertures depend.
• the walls of the apertures form funnels or Venturi channels as is well-known in the art.
• the smallest distance between neighbouring large apertures regardless of their particular shape and size is preferably at least 1.0 mm, more preferably 1.5 mm. This distance is measured on the surface of the film on the side closest to the user facing surface of the absorbent article.
• the film material is preferably rendered hydrophilic to such a degree that the contact angle is less than 90° with distilled water upon first contact with the water.
• this can be achieved by surfactant treatment.
• surfactant treated polymeric films providing the first layer it has been found that it is beneficial to use films where the surfactant is permanently fixed on the film surface. These are so-called film materials with resin integrated surfactant. For these films even repeated wetting by distilled water would provide approximately the same contact angle as the first contact with distilled water.
• the wearer facing surface is treated with an agent such that liquids are directed towards the apertures.
• agents can be silicon or teflon which provide the treated surface with a self-cleaning effect. This treatment can be in addition to the above mentioned surfactant treatment.
• Films such as those disclosed in EP-O 205 286, EP-0-165 208, EP-0-18 020, EP-0-59 506 or US-3,929,135 are explicitly referred to as suitable as first passage layer of the topsheet provided the requirements of the claims are met.
• Other suitable formed films, provided the requirements for the first passage layer are met, are described in U.S. Patent 4,324,246, U.S. Patent 4,342,314, U.S. Patent 4,463,045 and U.S. Patent 5,006,394.
• Particularly preferred microaperturing of formed film is disclosed in U.S. patent 4,609,518 and U.S. patent 4,629,643.
• These microapertures can also be included in the first passage layer of the topsheet provided they are less than 0.15 mm 2 and hence essentially provide breathability. Ways of making such films are well-known in the art and have also been disclosed in the above prior art references.
• the second passage layer of the topsheet is provided by a second film material having apertures.
• the second passage layer also is typically as large as the first passage layer but can be present in the center (longitudinal and/or transverse) only, or alternatively extend beyond the perimeter of the first passage layer, particularly in the region of the wings or side wrapping elements if these are present.
• this second passage layer can be identical to the first passage layer film except that large apertures should preferably be avoided or if some large apertures are present they should only be aligned with the large apertures in the first layer for up to 10% total open area, otherwise that could cause rewet and masking issues.
• the second film layer can have simple apertures which have no part of their walls depend from one surface of the film.
• the second film material is at least as hydrophilic as the film material of the first layer in order to present no barrier for the liquid. Better yet it is more hydrophilic (or less hydrophobic) than the first film and creates a directing force for the liquid towards the absorbent structure after passing the first layer.
• both layers have about the same total open area.
• the second layer has 10% larger, most preferably a more than 20% larger total open area than the first film layer.

Landscapes

• Health & Medical Sciences (AREA)
• Epidemiology (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Vascular Medicine (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Absorbent Articles And Supports Therefor (AREA)
• Orthopedics, Nursing, And Contraception (AREA)
• Laminated Bodies (AREA)

Priority Applications (8)

Applications Claiming Priority (3)

Publications (2)

Family

ID=26138993

Family Applications (1)

Country Status (8)

Cited By (11)

Families Citing this family (10)

Citations (5)

Family Cites Families (2)

• 1995
  • 1995-12-22 EP EP95120497A patent/EP0749738B1/fr not_active Expired - Lifetime
• 1996
  • 1996-05-16 JP JP50306097A patent/JP4031034B2/ja not_active Expired - Fee Related
  • 1996-05-16 WO PCT/US1996/007032 patent/WO1997000057A1/fr active IP Right Grant
  • 1996-05-16 CA CA002225098A patent/CA2225098C/fr not_active Expired - Fee Related
  • 1996-05-16 KR KR1019970709483A patent/KR100415036B1/ko not_active IP Right Cessation
  • 1996-05-16 AU AU57512/96A patent/AU701628B2/en not_active Ceased
  • 1996-06-19 AR ARP960103199A patent/AR002512A1/es unknown
  • 1996-08-21 TW TW085110220A patent/TW354253B/zh active

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